A turret can have a circular top with crenellations as in the picture at right, a pointed roof, or other kind of apex. It might contain a staircase if it projects higher than the building; however, a turret is not necessarily higher than the rest of the building; in this case, it is typically part of a room, that can be simply walked into – see the turret of Chateau de Chaumont on this collection of turrets, which also illustrates a turret on a modern skyscraper.

A building may have both towers and turrets; turrets might be smaller or higher but the difference is generally considered to be that a turret projects from the edge of the building, rather than continuing to the ground. The size of a turret is therefore limited by technology, since it puts additional stresses on the structure of the building. It would traditionally be supported by a corbel.